Method and arrangement for removing noise and measurements of head-media spacing modulation for digital recording

摘要

A method and arrangement for measuring head-media spacing modulation (HMS_Wq) employs a profilometer to measure the surface topography of a disk. A cumulative power spectral density (PSD) distribution is generated from the measured surface topography. Discontinuities and steps are identified in the PSD distribution. The discontinuities and steps are removed to create a corrected PSD distribution. A noise free spectrum is then reconstructed from the corrected PSD distribution.